Cyanid compound and process of making same.



j UNITED STATES PATENT FFICE.

GEORG' ERLW'EIN AND ALBERT FRANK; OF BERLIN, GERMANY.

CYANID-COMPOU'ND AND-.PROCES'S-OF MAKING SAME.

SPECIFICATION forming part of Letters Patent'No. 708,333, dated September 2, 1902.

I Application filed February 27, 1902. Serial No. 95,935. (No specimens.) 7

T aZZ whom it mag/concern.-

Be it known that we, GEORG ERLWEIN and". ALBERT FRANK,doctors of chemistry,subj ects of the German Emperor, residing at 88 Markgrafenstrasse, Berlin, Germany, have invented certain new and useful Improvements in Oyanid Compounds and Processes of Making Same; and We do hereby declare the follow-' ing to be a full, clear, and exact description I0 skilled in the art to which it appertains to "make and use the same.

' The object of our invention is a composiQ tion containing cyanid of calcium destined [5 to serve as a substitute for cyanid of potassium in lixiviating the ores or materials containing precious metals; and, further, ourin: vention relates to aprocess of manufacturing this composition. The composition according toour invention consists in a' molten mass of cyanid of cal cium and of a metallic chlorid which may be ONNOa o Ca (01x0 Cyauamid of calcium l- Carbon Cyanid of calcium.

The action of the metallic chlorid consists in favoring the regular course of the reaction, and especially in avoiding the foaming of the reacting mass, and, further, in favoring the lixiviation of .the precious metals by the cyanid of calcium contained in the said composition. The mass is particularly suitable v for leaching slimes and failings even though they contain silver.

Asuitable proportion of the ingredients we employ tomake our composition consists of onepart of cyanid of calcium and two and tothe qualities which he intends to give the mass. llowev'er, it is not to be recomof the invention, such as will enable othersdium; but we may also employ a larger or smaller proportion of the metallic chlorid.

The skilled Workman may choose the proportions according to the course of the process 5 ture of cyanamid ofcalcium, carbon, and

metallic chlorid to a suitable temperature,

which temperature we maintain until the foaming of the molten mass ceases, which occurs after from half an hour to one hour. Then the mass may be scooped out from the vessel inwhich the process is carried out, or the mass may be poured out or removed in any other suitable manner, so as to cool it down on a cool support. We also may 0001 the mass in the vessel and remove the same after cooling.

The cyanamid of calcium which we employ according to our process is advantageously obtained from the carbid by the action of nitrogen, which we pass over carbid of calcium at a suitable high temperature. We have found that a cyanamid of calcium obtained by the action of nitrogen on carbid of calcium and carbon is especially suitable for our purpose. The composition may also be directly usedz'. 2., without previously purifying itfor the manufacture of hydrocyanic acid by treating the composition by acidsfor instance, hydrochloric acid.

Instead of cyanamid of calcium obtained from carbid of calcium and nitrogen to make our composition we also may employ cyanamid of calcium which is made in usual manner. When cyanamid of calcium obtained from carbid of calcium is employed, the fun ther addition of carbon may be omitted'in most cases, because the mass which results from the action of the nitrogen on carbid of calcium mostly contains free carbon, the reaction of nitrogen on the carbid being as follows:

OaC 2N CNNCa o;

Cal-bid of calcium Nitrogen (Jyanamid of calcium +Carbon.

Having now particularly described and ascertained the nature of our said invention' and the manner in which the same is to be performed, we declare that what we claim is 1. Composition containing cyanid of cal-' cium destined to serve as a substitute for cyanids of the alkalies consisting in a molten mass of cyanid of calcium and a metallic chlorid.

2. Composition containing cyanid of calcium destined to serve as a substitute for cyanids of the alkalies consisting in a molten 

